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There has been considerable development in the field of ocean waves with respect to the analytical, numerical and experimental aspects of the subject. The book contains seven articles by leading authors in the field. Chapter 1 is concerned with the time harmonic linearised theory of water waves and structures. Chapter 2 considers a complete second-order diffraction theory which is formulated for computing second-order wave loads on floating bodies in regular waves (applied to tension leg platform). Chapter 3 covers radiation and diffraction problems in the linearised theory of water waves and in Chapter 4, Painleve analysis, stretching transformations and Lie group analysis are employed to investigate the solutions of the Melnikov equations. An estimation of the hydrodynamic forces to the second-order are the subject of Chapter 5. The sixth chapter presents a discussion of the general problem of the non-linear interaction of ideal fluid free surface waves with fixed or moving impermeable bodies. The final chapter covers variational inequalities in physical oceanography.

Tsetse flies by transmitting disease prevent stock farming and the use of draught animals over some 10 km2 of Africa thereby restricting agro-economic development south of the Sahara to the level of the head-load and the hand hoe. They feed exclusively on vertebrae blood. As the host animals are usually invisible at more than a few metres' range the fly must hunt by smell. The flies find their blood meals by a combination of visually hunting for their hosts and navigating upwind (anemotaxis) when they smell host odour. Their problem is the confusing relationship between host direction odour movement through vegetation and wind speed. As the straightness of the displacement of packets of air downwind through the bush improves with wind speed one would predict that as the wind increases in speed the flies should find it progressively easier to locate invisible upwind hosts by odour-guided anemotaxis - at least over the lower range of the distribution of winds typical of the tsetse habitat. An investigation of this hypothesis is reported. Materials and methods are presented. Results are given and discussed.

A review of fire and explosion engineering is presented. Phase 1 highlighted major gaps in the knowledge of these phenomena. Phase 2 performed full-scale fire and explosion experiments. While there are numerous computer models used to predict the magnitude and severity of offshore fires and explosions these models have in general only been validated against small- and medium-scale costs due to the lack of full-scale experimental data. To assess the abilities of the range of computer models fire and explosion modellers have made blind predictions for the Phase 2 experiments. These predictions are being evaluated in accordance with the recently developed EC MEGGE Protocol (Model Evaluation Group - Gas Explosions). The availability of realistic full-scale experimental data and an improved set of predictive models will significantly enhance the ability of engineers to design against accidental fire and explosion events offshore. Tables photographs and graphs are presented on pages 11 to 15.

This book is designed to help the doctor who has to provide medical care for the expanding offshore oil industry. It describes the pattern of work offshore and the medical problems which it generates. The special features of offshore medical care are described along with the training of medics, the design of hospital facilities, and the provision of back-up services to cope with them. There are special chapters on diving, hygiene and catering, dentistry and legal aspects.

Conf held 6-9 May 1991 in Houston USA Papers are Analysis of vortex-induced motions and drag for moored bluff bodies The application of regulations for certificate of fitness of jackup structures in the British sector of the North Sea Observed storm stability of jackup boats (lifeboats) Verification of jackup leg- to-hull beam model interaction using super elements The jackup monopile - a production drilling platform Findings from a joint industry study on foundation fixity of jackup units Loss control by subsea barrier valve for offshore gas pipeline Installation of subsea isolation valves - a review of recent operations in the North Sea Diverless maintenance of a subsea barrier valve Snorre TLP topside design Snorre TLP configuration and analysis technology Snorre TLP tethers and foundation Snorre riser and well system

The prepardedness for the response to and early lessons learned from the Exxon Valdez incident are discussed. A number of important environmental energy economic and health implications are addressed. Findings include: prevention is the first line of defence prepardedness must be strengthened response capabilities must be enhanced to reduce environmental risk some oil spills may be inevitable legislation on liability and compensation is needed the United States should ratify the IMO 1984 protocols federal planning for oil spills must be improved and studies of the long-term environmental and health effects must be undertaken expeditiously and carefully.

Dangerous cargoes lost in the North Sea must be salvaged before they can cause accidents. Lost cargoes must be found using sonar and then identified with still and video cameras mounted on a ROV (remotely operated vehicle). Finally the cargoes must be salvaged or neutralised. The practice of search location selection identification and salvage of cargoes and dangerous goods lost in the Dutch sector of the North Sea is presented. Special attention is paid to technical and operational aspects of locating and identifying lost cargoes. The application of a diver a swimming ROV or a seabed crawling ROV for these operations is examined. Two recent search and salvage cases using a ROV are elaborated.

Funnel web spiders build flat solidly woven webs which converge in a funnel-like retreat. This protects the spider and hides from prospective predators. The spider leaves its lair for predation and maintaining the web. To survive it can be necessary for the spider to return to the retreat from every spot of the web as quick as possible and therefore on a straight course. These spiders have therefore evolved several orientation mechanisms. Although some research has been undertaken there is no indication that the spider orientates by means of cues such as odour gradients or the electromagnetic field. An investigation is presented which has been carried out to confirm the importance of idiothetic orientation in the spider's homing behaviour. It shows the meaning of cues from the web for its ability to return to its lair. Methods are presented and results discussed and conclusions drawn.

The art of applying the optical principles embodied in the telescope, prisms and mirrors to mechanical measurement and workshop assembly is termed 'Optical Alignment' or 'Optical Tooling'. The particular optical instruments described in this manual are the micro-alignment telescope and its accessories, manufactured by Rank Taylor Hobson of the Rank Organisation. The manual provides guidance in its operation and application. Contents comprise of chapters on: Basic principles of optics, Equipment specification (telescope and mountings, targets, levels, collimator, optical squares), The telescope and targets, Auto-reflection, auto-collimation and projection, Collimation, Levels, Optical squares, Maintenance and field checks, Designing for optical alignment and Applications.

Azimuth thrusters have been in use for 30-40 years and gained the market lead on more conventional propulsion systems during the last decade. Design developments are discussed including pusher-type and puller-type and advantages of the pulling mode are considered. The Azipull(r) concept was to develop a low drag high efficiency pulling thrusters that can be linked to any kind of prime mover and located anywhere in the ship except the pod. The potential of Azipull(r) in the marine market is discussed. Highlights from initial computational fluid dynamics (CFD) calculations and model tests are described. The use of Azipull(r) concept in conjunction with a novel double ended aluminium catamaran ferry is explored.

This paper presents the solution of the optimized problem of designing the high-speed catamarans that applies limiting on heights of the wash waves generated by the high-speed catamarans. The definition of the problem is initiated by the requirements to coastal and inland navigation. The known experience of the operation of the high-speed ships in Russia Canada and Great Britain corroborates the actuality of such definition of the design problem. The confirmation of the known fact of reduction of level of the wave effect under hydrodynamic relief of the high-speed catamarans by hydrofoils has been obtained. The use of the factor of limiting the wash waves at the design stage of high-speed ships will favour the development and spreading of high-speed shipping in coastwise areas and inland waterways.

Ozone is a photochemical pollutant produced as a result of complex reactions among NOX (nitrogen oxides) ad VOCs (volatile organic compounds) in the presence of sunlight. High ozone levels cause human health problems and damage plants and certain materials and long exposure to ozone increases the negative effects. Part of some research work supported by the Basque government is presented. This work analyses the evolution of O3 (tropospheric ozone) concentrations measured in five stations located on the coast of the Basque Country (North Central Spain) during 2001-2004. The air quality data monitored is considered. Results are presented and discussed. It is concluded that the air quality of Kostaldea relative to ozone from 2001 to 2004 was of good quality with specific episodes.

In this paper the dynamic response of a marine riser due to vortex shedding is numerically investigated. The riser is divided in two-dimensional sections along the riser length. The Discrete Vortex Method is employed for the assessment of the hydrodynamic forces acting on these two-dimensional sections. The hydrodynamic sections are solved independently and the coupling among the sections is taken into account by the solution of the structure in the time domain by the Finite Element Method. Parallel processing is used to improve the performance of the method. A master-slave approach via MPI - Message Passing Interface - is used to exploit the parallelism of the present code. Scalability of the algorithm is shown and discussed.

Two different wave configurations RR (regular reflection) and MR (Mach reflection) are possible in steady shock wave reflection. Parallel numerical simulations are carried out to study the effects of pulsed laser energy deposition on steady RR and MR. A single laser pulse is focused upstream of the incident shock waves. It causes the formation of a hot-spot region and a blast wave which interacts in a complex way with a steady shock wave reflection pattern. It is found that the laser energy addition in the free stream can force the transition between regular and Mach reflections in the dual solution domain. Results are presented and conclusions drawn.

With the advances in science and technology we are becoming surrounded by a vast number of electronic devices. Most of these communicate with each other through data signal or simply energy transmission which is sent by electrical cables. Most of these devices work at such frequencies that can actually create harmonic disturbance. The traditional way of reducing this disturbance is to use passive LC filters. These have to be correctly sized in order to avoid dangerous resonances in the distribution system. Nowadays active filters may be used based on forced commutation converters to compensate for many types of disturbance such as harmonic current or unbalanced loads and reactive power. The traditional passive LC filters are compared to the active compensation devices and some numerical simulations are presented to analyse the dynamic behaviour of the proposed solutions. Conclusions are drawn.

This paper considers large scattered arrays for 3D underwater acoustic positioning and imaging where the hydrophone sensors in the array form a network over the total area of interest. A method where the Generalized Cross Correlation (GCC) function is projected over the volume is being used and 3D images are formed. In this paper an attempt is made to determine the discretization of these images so that they fulfill the Nyqvist criterion. In order to detect and position targets by scattered sensors it is important to Doppler compensate and weight the different sensor pair results. In this paper the water is divided into volumes where Doppler compensation and pair weightings are implemented for each volume individually. Various aspects can govern the weighting assigned to a sensor pair and in this paper use has been made of the opening angle between sensor pair and target. The baseline of the sensor pairs varies from 17 - 181 meters therefore different frequency bandwidths for each sensor pair is used. The developed method is tested on both simulations and real measurement for a surface target.

Synthetic aperture processing techniques are presented and applied to results from an at-sea trial of an autonomous underwater vehicle (AUV) towed hydrophone array system in Nantucket Sound. The experiment consisted of a source deployed from a moored ship and the AUV towing the array outward from the source on a straight radial track. During the experiment a ferry passed through the shipping channel from the main land of Cape Cod to Nantucket Harbour and provided a "target of opportunity" emitting both broadband and narrow band sound. Estimates of the limits of coherent processing with a synthetic aperture are presented which indicate sufficient coherence in the shallow water multi-path environment to form a reasonable synthetic aperture. Both conventional and Kalman filter tracking techniques are theoretically presented and applied to the radiated noise of the vehicle. Further the benefit of using the joint estimation scheme is shown by a decrease in variance of the bearing estimate for the target when compared to the conventional scheme.

Intellectually all those associated with the Exploration and Production business can articulate the critical role that people play in an industry which is risk-based and capital intensive. With demographic pressures and fewer students pursuing science and technology in the developed world the criticality of attracting developing and retaining people is paramount. In the developing world there is often an ample supply of graduates however the challenge of building real capability and experience cannot be underestimated. Against the background of the global challenges it is proposed that people be viewed much more as a part of sustainable development. The classic sustainable development model comprising of economics the environment and the community has people at every level. To achieve the goal of a long-term sustainable contribution from the people currently in the industry and those considering joining will take a major shift from some of the development models currently employed. The significance of a competent trained and motivated workforce is examined against the background of the SD principles. The themes developed are based on extensive contact and discussions with both National and International oil and gas companies around the globe.

A new control strategy has been developed for liquid level control by using a gas control valve (GCV) on the gas leg. A linearized mathematical model has been derived for the controller design of the gas control loop. The control system design has been conducted for stability and transient response characteristics and its performance is verified by simulating the integrated control system for slug input. A detailed experimental study has been conducted using a newly developed Gas Liquid Cylindrical Cyclone (GLCC) with active control system and a computerized data acquisition system. Time responses for integrated liquid level and pressure control system and GLCC operational envelopes for liquid carry-over and gas carry-under are determined experimentally.

A study was undertaken to determine if oblique incidence ultrasonic C-scans could predict changes in the tensile properties of carbon-epoxy laminates that had been subjected to low level impacts. Angle-ply laminates were manufactured to provide roughly a 3:1 ratio of longitudinal-to-transverse extensional stiffness. The specimens were divided into two groups for impacting a delamination group and a rigid group. After impacting each specimen underwent a normal incidence C-scan and an oblique incidence C-scan using a focusing transducer to reduce beam spread. The normal incidence scan was used to map the damage area and the oblique incidence scan was used to quantify the changes in extensional stiffness. Tensile tests were performed on each specimen and strength extensional stiffness and Poisson's ratios were determined.